The records are being sought by journalists and public interest groups to help determine who is influencing White House policy on health care, the economy and a host of other issues.

Under the Obama policy, most of the names of visitors from Inauguration Day in January through the end of September will never be released. After the Secret Service and the White House denied a request for those records, Judicial Watch filed suit on Monday in federal court in Washington.

Like the Bush administration before it, the Obama White House argues that the visitor records belong to the White House, not the Secret Service. White House records are not subject to the Freedom of Information Act, as agency records would be. Federal Judge Royce C. Lamberth ruled twice during the Bush administration that White House visitor logs belong to the Secret Service, which creates and maintains them, and must be released.

To settle lawsuits against the Bush and Obama administrations, filed by the liberal group Citizens for Responsibility and Ethics in Washington, or CREW, the Obama administration has released the names of hundreds of visitors, out of the hundreds of thousands who have been to the White House for meetings, events or tours. The administration has promised to release more of the names of visitors for the period from October onward. The first wave of records is due near the end of this year.

Even for the names it has released, the White House has not provided a city or affiliation, such as a company name or organization represented, making it difficult or impossible to tell whether a person named on the list is a well-known person with that name. And some names are not being released at all, including potential Supreme Court nominees, personal guests of the first family and certain security officials.

The White House has set up a Web page where members of the public can request the release of names of visitors, but that system gives results only for the names of visitors that the public can guess. If the public can't guess who may have visited the White House between January and September, it can't find out the names.

In addition, although the White House system requires requesters to submit their e-mail address, requests are not acknowledged by the White House, and no reply is sent to the requesters. The names sought, if they correspond to actual visitors, just show up in the next batch of names released by the White House. So far, each release of names by the White House has happened on the evening before a holiday, the classic Washington tactic for burying uncomfortable news.

Negotiations with White HouseJudicial Watch, in a press release, described being invited to the White House to discuss its request. It met on Oct. 27 with Norman L. Eisen, special counsel to the president, who happens to be a founder of CREW, which had dropped its own lawsuits on this issue.

"During the meeting, the Obama White House officials asked Judicial Watch to scale back its request and expressed hope that Judicial Watch would publicly praise the Obama administration’s commitment to transparency," Judicial Watch said. "However, the White House refused to abandon its legally indefensible line of reasoning that White House visitor logs are not subject to FOIA law.

"If the Obama administration is serious about transparency, they will agree to the release of these records under the Freedom of Information Act," said Judicial Watch President Tom Fitton.

White House officials did not reply Wednesday to a request for comment on the Judicial Watch lawsuit.

Request by msnbc.com also deniedA similar request by msnbc.com was rejected by the Secret Service, which referred us to the White House, which also denied the request. The Secret Service denied an administrative appeal of msnbc.com's request on Monday.

The White House now says that national security is a reason not to release the records for January through September, an issue not raised by the Bush or Obama administrations in their previous legal filings on this issue.

"The inherited visitor entrance system was not structured to identify sensitive records," Eisen wrote to msnbc.com. "As a result, we cannot make a broad retroactive release of White House visitor records without raising profound national security concerns. For example, the release of certain sensitive national security records encompassed in your request could assist foreign intelligence agencies to identify and target U.S. government officials working on sensitive national security issues."

Background on this issue is in our previous stories, at the links below. Documents related to the cases are in the box accompanying this article.